Back to Repositories

Validating Diagram Generation and Node Relationships in mingrammer/diagrams

This test suite validates the core functionality of the diagrams library, focusing on diagram creation, cluster management, and edge connections. It ensures proper handling of diagram directionality, formatting, and node relationships while maintaining code quality and test coverage.

Test Coverage Overview

The test suite provides comprehensive coverage of the diagrams library’s core components:

Diagram validation including direction, curve style, and output format
Cluster management and nested cluster behavior
Node relationship and connection testing
Edge attribute handling and directional connections
Resource folder structure validation

Implementation Analysis

The testing approach utilizes Python’s unittest framework with a structured class-based organization. Each test class focuses on a specific component (DiagramTest, ClusterTest, EdgeTest, ResourcesTest) with setUp/tearDown methods for proper test isolation. The implementation leverages unittest assertions and context managers for thorough validation.

Technical Details

Key technical components include:

unittest framework for test organization
File system operations for cleanup and validation
Context managers for diagram and cluster scope management
Custom assertion methods for relationship validation
Resource path handling using pathlib

Best Practices Demonstrated

The test suite exemplifies several testing best practices:

Proper test isolation through setUp/tearDown methods
Comprehensive edge case coverage
Clear test method naming conventions
Efficient resource cleanup
Modular test organization by component

mingrammer/diagrams

tests/test_diagram.py

            
import os
import pathlib
import shutil
import unittest

from diagrams import Cluster, Diagram, Edge, Node, getcluster, getdiagram, setcluster, setdiagram


class DiagramTest(unittest.TestCase):
    def setUp(self):
        self.name = "diagram_test"

    def tearDown(self):
        setdiagram(None)
        setcluster(None)
        # Only some tests generate the image file.
        try:
            shutil.rmtree(self.name)
        except OSError:
            # Consider it file
            try:
                os.remove(self.name + ".png")
            except FileNotFoundError:
                pass

    def test_validate_direction(self):
        # Normal directions.
        for dir in ("TB", "BT", "LR", "RL", "tb"):
            Diagram(direction=dir)

        # Invalid directions.
        for dir in ("BR", "TL", "Unknown"):
            with self.assertRaises(ValueError):
                Diagram(direction=dir)

    def test_validate_curvestyle(self):
        # Normal directions.
        for cvs in ("ortho", "curved", "CURVED"):
            Diagram(curvestyle=cvs)

        # Invalid directions.
        for cvs in ("tangent", "unknown"):
            with self.assertRaises(ValueError):
                Diagram(curvestyle=cvs)

    def test_validate_outformat(self):
        # Normal output formats.
        for fmt in ("png", "jpg", "svg", "pdf", "PNG", "dot"):
            Diagram(outformat=fmt)

        # Invalid output formats.
        for fmt in ("pnp", "jpe", "unknown"):
            with self.assertRaises(ValueError):
                Diagram(outformat=fmt)

    def test_with_global_context(self):
        self.assertIsNone(getdiagram())
        with Diagram(name=os.path.join(self.name, "with_global_context"), show=False):
            self.assertIsNotNone(getdiagram())
        self.assertIsNone(getdiagram())

    def test_node_not_in_diagram(self):
        # Node must be belong to a diagrams.
        with self.assertRaises(EnvironmentError):
            Node("node")

    def test_node_to_node(self):
        with Diagram(name=os.path.join(self.name, "node_to_node"), show=False):
            node1 = Node("node1")
            node2 = Node("node2")
            self.assertEqual(node1 - node2, node2)
            self.assertEqual(node1 >> node2, node2)
            self.assertEqual(node1 << node2, node2)

    def test_node_to_nodes(self):
        with Diagram(name=os.path.join(self.name, "node_to_nodes"), show=False):
            node1 = Node("node1")
            nodes = [Node("node2"), Node("node3")]
            self.assertEqual(node1 - nodes, nodes)
            self.assertEqual(node1 >> nodes, nodes)
            self.assertEqual(node1 << nodes, nodes)

    def test_nodes_to_node(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node"), show=False):
            node1 = Node("node1")
            nodes = [Node("node2"), Node("node3")]
            self.assertEqual(nodes - node1, node1)
            self.assertEqual(nodes >> node1, node1)
            self.assertEqual(nodes << node1, node1)

    def test_default_filename(self):
        self.name = "example_1"
        with Diagram(name="Example 1", show=False):
            Node("node1")
        self.assertTrue(os.path.exists(f"{self.name}.png"))

    def test_custom_filename(self):
        self.name = "my_custom_name"
        with Diagram(name="Example 1", filename=self.name, show=False):
            Node("node1")
        self.assertTrue(os.path.exists(f"{self.name}.png"))

    def test_empty_name(self):
        """Check that providing an empty name don't crash, but save in a diagrams_image.xxx file."""
        self.name = "diagrams_image"
        with Diagram(show=False):
            Node("node1")
        self.assertTrue(os.path.exists(f"{self.name}.png"))

    def test_autolabel(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node"), show=False):
            node1 = Node("node1")
            self.assertTrue(node1.label, "Node
node1")

    def test_outformat_list(self):
        """Check that outformat render all the files from the list."""
        self.name = "diagrams_image"
        with Diagram(show=False, outformat=["dot", "png"]):
            Node("node1")
        # both files must exist
        self.assertTrue(os.path.exists(f"{self.name}.png"))
        self.assertTrue(os.path.exists(f"{self.name}.dot"))

        # clean the dot file as it only generated here
        os.remove(self.name + ".dot")


class ClusterTest(unittest.TestCase):
    def setUp(self):
        self.name = "cluster_test"

    def tearDown(self):
        setdiagram(None)
        setcluster(None)
        # Only some tests generate the image file.
        try:
            shutil.rmtree(self.name)
        except OSError:
            pass

    def test_validate_direction(self):
        # Normal directions.
        for dir in ("TB", "BT", "LR", "RL"):
            with Diagram(name=os.path.join(self.name, "validate_direction"), show=False):
                Cluster(direction=dir)

        # Invalid directions.
        for dir in ("BR", "TL", "Unknown"):
            with self.assertRaises(ValueError):
                with Diagram(name=os.path.join(self.name, "validate_direction"), show=False):
                    Cluster(direction=dir)

    def test_with_global_context(self):
        with Diagram(name=os.path.join(self.name, "with_global_context"), show=False):
            self.assertIsNone(getcluster())
            with Cluster():
                self.assertIsNotNone(getcluster())
            self.assertIsNone(getcluster())

    def test_with_nested_cluster(self):
        with Diagram(name=os.path.join(self.name, "with_nested_cluster"), show=False):
            self.assertIsNone(getcluster())
            with Cluster() as c1:
                self.assertEqual(c1, getcluster())
                with Cluster() as c2:
                    self.assertEqual(c2, getcluster())
                self.assertEqual(c1, getcluster())
            self.assertIsNone(getcluster())

    def test_node_not_in_diagram(self):
        # Node must be belong to a diagrams.
        with self.assertRaises(EnvironmentError):
            Node("node")

    def test_node_to_node(self):
        with Diagram(name=os.path.join(self.name, "node_to_node"), show=False):
            with Cluster():
                node1 = Node("node1")
                node2 = Node("node2")
                self.assertEqual(node1 - node2, node2)
                self.assertEqual(node1 >> node2, node2)
                self.assertEqual(node1 << node2, node2)

    def test_node_to_nodes(self):
        with Diagram(name=os.path.join(self.name, "node_to_nodes"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(node1 - nodes, nodes)
                self.assertEqual(node1 >> nodes, nodes)
                self.assertEqual(node1 << nodes, nodes)

    def test_nodes_to_node(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(nodes - node1, node1)
                self.assertEqual(nodes >> node1, node1)
                self.assertEqual(nodes << node1, node1)


class EdgeTest(unittest.TestCase):
    def setUp(self):
        self.name = "edge_test"

    def tearDown(self):
        setdiagram(None)
        setcluster(None)
        # Only some tests generate the image file.
        try:
            shutil.rmtree(self.name)
        except OSError:
            pass

    def test_node_to_node(self):
        with Diagram(name=os.path.join(self.name, "node_to_node"), show=False):
            node1 = Node("node1")
            node2 = Node("node2")
            self.assertEqual(node1 - Edge(color="red") - node2, node2)

    def test_node_to_nodes(self):
        with Diagram(name=os.path.join(self.name, "node_to_nodes"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(node1 - Edge(color="red") - nodes, nodes)

    def test_nodes_to_node(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(nodes - Edge(color="red") - node1, node1)

    def test_nodes_to_node_with_additional_attributes(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node_with_additional_attributes"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(
                    nodes -
                    Edge(
                        color="red") -
                    Edge(
                        color="green") -
                    node1,
                    node1)

    def test_node_to_node_with_attributes(self):
        with Diagram(name=os.path.join(self.name, "node_to_node_with_attributes"), show=False):
            with Cluster():
                node1 = Node("node1")
                node2 = Node("node2")
                self.assertEqual(
                    node1 << Edge(
                        color="red",
                        label="1.1") << node2,
                    node2)
                self.assertEqual(
                    node1 >> Edge(
                        color="green",
                        label="1.2") >> node2,
                    node2)
                self.assertEqual(
                    node1 << Edge(
                        color="blue",
                        label="1.3") >> node2,
                    node2)

    def test_node_to_node_with_additional_attributes(self):
        with Diagram(name=os.path.join(self.name, "node_to_node_with_additional_attributes"), show=False):
            with Cluster():
                node1 = Node("node1")
                node2 = Node("node2")
                self.assertEqual(
                    node1 << Edge(
                        color="red",
                        label="2.1") << Edge(
                        color="blue") << node2,
                    node2)
                self.assertEqual(
                    node1 >> Edge(
                        color="green",
                        label="2.2") >> Edge(
                        color="red") >> node2,
                    node2)
                self.assertEqual(
                    node1 << Edge(
                        color="blue",
                        label="2.3") >> Edge(
                        color="black") >> node2,
                    node2)

    def test_nodes_to_node_with_attributes_loop(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node_with_attributes_loop"), show=False):
            with Cluster():
                node = Node("node")
                self.assertEqual(
                    node >> Edge(
                        color="red",
                        label="3.1") >> node,
                    node)
                self.assertEqual(
                    node << Edge(
                        color="green",
                        label="3.2") << node,
                    node)
                self.assertEqual(
                    node >> Edge(
                        color="blue",
                        label="3.3") << node,
                    node)
                self.assertEqual(
                    node << Edge(
                        color="pink",
                        label="3.4") >> node,
                    node)

    def test_nodes_to_node_with_attributes_bothdirectional(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node_with_attributes_bothdirectional"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(
                    nodes << Edge(
                        color="green",
                        label="4") >> node1,
                    node1)

    def test_nodes_to_node_with_attributes_bidirectional(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node_with_attributes_bidirectional"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(
                    nodes << Edge(
                        color="blue",
                        label="5") >> node1,
                    node1)

    def test_nodes_to_node_with_attributes_onedirectional(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node_with_attributes_onedirectional"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(
                    nodes >> Edge(
                        color="red",
                        label="6.1") >> node1,
                    node1)
                self.assertEqual(
                    nodes << Edge(
                        color="green",
                        label="6.2") << node1,
                    node1)

    def test_nodes_to_node_with_additional_attributes_directional(self):
        with Diagram(name=os.path.join(self.name, "nodes_to_node_with_additional_attributes_directional"), show=False):
            with Cluster():
                node1 = Node("node1")
                nodes = [Node("node2"), Node("node3")]
                self.assertEqual(
                    nodes >> Edge(
                        color="red",
                        label="6.1") >> Edge(
                        color="blue",
                        label="6.2") >> node1,
                    node1)
                self.assertEqual(
                    nodes << Edge(
                        color="green",
                        label="6.3") << Edge(
                        color="pink",
                        label="6.4") << node1,
                    node1)


class ResourcesTest(unittest.TestCase):
    def test_folder_depth(self):
        """
        The code currently only handles resource folders up to a dir depth of 2
        i.e. resources/<provider>/<type>/<image>, so check that this depth isn't
        exceeded.
        """
        resources_dir = pathlib.Path(__file__).parent.parent / "resources"
        max_depth = max(
            os.path.relpath(
                d,
                resources_dir).count(
                os.sep) +
            1 for d,
            _,
            _ in os.walk(resources_dir))
        self.assertLessEqual(max_depth, 2)